1. Field of the Invention
The present invention relates to new and useful improvements in fluid energy conservation devices for harnessing fluid energy and, more particularly, to a modular fluid turbine installation for transforming fluid energies such as wind currents into a usable rotational force and for storing any excess energy generated by the fluid turbine installation.
2. Background Art
Energy needs of our society continue to grow at an increasing rate. Unfortunately, much of this energy is supplied by nonrenewable resources whose relative availability continues to decrease. Members of the power generation industry are gradually developing more efficient methods of power generation, with the ambition of one day generating their electricity from clean, sustainable renewable resources.
One such potential area for expansion is wind energy. Wind turbines of various sizes and designs can mitigate our dependence on foreign energy supplies while providing distinct benefits to our domestic economy. Wind turbine designs may be optimized for particular locations and conditions. Moreover, wind turbines use the wind, a clean, nonpolluting energy source.
The United States has tremendous wind energy resources. In California, wind farms currently replace almost 4 million barrels of oil per year. At least sixteen states have even greater wind potential than California based on measured average wind rates.
The installed wind energy generating capacity in the U.S. is currently estimated to be around 6,400 MW, and was expected to generate about 16.7 billion kWh of electricity in 2004, which was less than about 1% of the total U.S. electricity generation at that time. By contrast, the total amount of electricity that could potentially be generated from wind in the United States has been estimated at about 11,000 billion kWh annually, over three times the electricity generated in the U.S. today.
Existing wind farms help demonstrate how wind energy can help meet growing needs for affordable, reliable power. Moreover, with continued government encouragement through, among other things, heightened technology transfer from national laboratories to the wind energy industry, wind energy is slated to become more economical than traditional fossil-fueled energy. Some estimate that wind related energy sources could provide at least six percent of the nation's electricity by 2020. More importantly, wind generators could help revitalize farms and rural communities without consuming any natural resource or emitting any pollution or greenhouse gases.
Wind turbines have traditionally been built using a turbine attached to a horizontal axis suspended high above the ground. Wind turbines have been used for centuries to capture the power of the wind to mill grain into flour or pump water. More recently, as previously indicated, wind generators; such as a wind turbine configured to produce electricity, have also been used to supplement the electrical energy supply.
As noted, windmills and other wind-driven power generating apparatus have long been known in the art. Such apparatus are exemplified by the windmills and wind motors disclosed, for example, in U.S. Pat. Nos. 1,234,405; 2,431,111; 4,134,707; 4,321,005; and 6,948,905. One type of windmill apparatus is conventionally constructed with a plurality of vertically stacked, individual segments of two or more wind wheels or wind rotors, each of which is adapted to be drivingly connected to a common output drive shaft. By increasing the number of individual segments connected to the drive shaft, the greater the driving force or torque and, thereby, the greater the power that can be generated with the apparatus.
The wind motor apparatus of U.S. Pat. No. 2,431,111 includes a manually-operated, jaw-type positive clutch for selectively connecting and disconnecting wind wheel segments in series depending on the magnitude of the wind force or the output power desired. In this way, the apparatus is said to be adapted for operation in low or high wind currents or for operating, for example, more than one power consuming mechanism.
U.S. Pat. Nos. 1,234,405 and 4,134,707 both disclose wind turbine apparatus which comprise discrete wind wheel segments joined together in a vertical stack to form a unitary wind turbine. As the segments are added, they are rigidly interconnected to either the drive shaft or to each other from the lowermost to the topmost segment.
It is also known in the art to employ a windshield or casing for covering a portion of the blades of a wind wheel rotor so that the wind stream impinges on only those blades which are properly oriented with respect to the wind direction. U.S. Pat. Nos. 1,460,114 and 2,059,356, for example, disclose wind wheels having shields mounted for rotation about the periphery of a wind rotor. Wind vanes connected to the shields are said to cause the shields to respond to wind direction in a manner to present the most favorable rotor aspect to the wind stream, as well as to shield the blades from the force of the wind when the velocity thereof becomes sufficiently high to cause damage to the wind wheel installation.
Wind power may also be generated by a horizontal windmill, where wind catching devices rotate in a horizontal plane about a vertical axis. In a horizontal windmill, the wind catching devices are moving in a direction counter to the direction of the wind for one half of their rotational cycle, so the driving force of such a windmill is determined by the difference between the force generated on the front surface of wind catchers moving in the direction of wind flow versus the force generated on the back surface of the wind catchers moving against the direction of wind flow. A number of challenges relating to cost and effectiveness of horizontal wind catchers have led to a number of different windmill constructions.
An object of the present invention is to provide a fluid energy conservation device for efficiently developing electrical power from a wide range of fluid energy sources.